FOREST PROTECTION 117 



apothecia in the succeeding spring. 

 The most important representative of 

 this family in Europe is Peziza. 

 III. Order Basidiomycetes. 



Spores carried on basidia of definite shape 

 and size, and bearing a fixed number of spores. 

 1st. Family — Uredinece. 



All are injurious parasites, the 

 mycelium being in the intercellular 

 spaces of the tissues (particularly in 

 the leaves) of higher plants. These 

 fungi change their hostplants, showing 

 a double generation, and develop sev- 

 eral kinds of asexual spores, according 

 to the season and to the host; aeeidio- 

 spores and pycnoconidia in spring; 

 uredospores in summer; teleutospores 

 in autumn, which in the following 

 spring develop basidiospores. The my- 

 celium from the basidiospores enters 

 the first host and develops the seci- 

 diuxn stage (formerly the gem* A* 

 cfidium) with aecidia and pycnidia. The 

 next stage on a different host develops 

 the uredospores (formerly genus Ure~ 

 do), and in autumn the thick walled 

 teleutospores. 



2nd. Family — Bymenomyceies. 



Basidia imbedded in a common 

 hymenium which clothes, in Agari- 

 cacece, a series of radial lamellae on the 

 under side of the pileus, and in Poly- 

 poracece and BoletacecB, the inner sur- 

 face of pores. 



In a few genera no distinctive 

 fructifications are formed (Exobasi- 

 dium vaccinii, parasitic and causing 

 hypertrophy on Ericacece). 



Another arrangement of the orders 

 and families of fungi might be made 

 with reference to pathogeny: 

 a. The groups 

 Ureamew 



Ustilaginece contain parasites only, 



(so-called "Smuts") I so that no proof of 

 Peronosporece [parasitism is required. 



Ema&cem 

 (witch broom) 



